(a) To qualify for retention in the commission's “deep-sea” register, a person included in such register must work as a longshoremen or as a checker, or make himself available for work in accordance with the provisions of subdivision (b) of this section, a minimum of 90 days in each half-calendar year, distributed at least 15 days to each month during at least five of the six months in each half-calendar year. In administering this section, receipt of compensation by any such person pursuant to the guaranteed wage provisions of any collective bargaining agreement relating to longshoremen and/or checkers shall be counted as constituting actual work, provided that such is received as a result of compliance with the provisions of subdivision (b) of this section.

(b) A registrant may make himself available for work by telephoning the THEIC between the hours of 4 p.m. and 8 p.m. on the prior day for orders. Those registrants who do not receive orders for the next day shall be available between the hours of 8 a.m. and 9 a.m. on the next day (except Saturday, Sunday or holidays) for telephone orders.

(c) To qualify for retention in the commission's “A” register, a person included in such register must appear on the current roster of an employer of such persons. Any such employer shall submit to the commission, at least once a year at a time designated by the commission, a roster of persons it employs or intends to employ.